interconnecting microfluidic package and fabrication

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University of Central Florida University of Central Florida STARS STARS UCF Patents Technology Transfer 8-2-2011 Interconnecting Microfluidic Package and Fabrication Method DIV Interconnecting Microfluidic Package and Fabrication Method DIV Hyoung Cho University of Central Florida Find similar works at: https://stars.library.ucf.edu/patents University of Central Florida Libraries http://library.ucf.edu This Patent is brought to you for free and open access by the Technology Transfer at STARS. It has been accepted for inclusion in UCF Patents by an authorized administrator of STARS. For more information, please contact [email protected]. Recommended Citation Recommended Citation Cho, Hyoung, "Interconnecting Microfluidic Package and Fabrication Method DIV" (2011). UCF Patents. 276. https://stars.library.ucf.edu/patents/276

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Page 1: Interconnecting Microfluidic Package and Fabrication

University of Central Florida University of Central Florida

STARS STARS

UCF Patents Technology Transfer

8-2-2011

Interconnecting Microfluidic Package and Fabrication Method DIV Interconnecting Microfluidic Package and Fabrication Method DIV

Hyoung Cho University of Central Florida

Find similar works at: https://stars.library.ucf.edu/patents

University of Central Florida Libraries http://library.ucf.edu

This Patent is brought to you for free and open access by the Technology Transfer at STARS. It has been accepted for

inclusion in UCF Patents by an authorized administrator of STARS. For more information, please contact

[email protected].

Recommended Citation Recommended Citation Cho, Hyoung, "Interconnecting Microfluidic Package and Fabrication Method DIV" (2011). UCF Patents. 276. https://stars.library.ucf.edu/patents/276

Page 2: Interconnecting Microfluidic Package and Fabrication

c12) United States Patent Cho

(54) INTERCONNECTING MICROFLUIDIC PACKAGE AND FABRICATION METHOD

(75) Inventor: Hyoung Jin Cho, Oviedo, FL (US)

(73) Assignee: University of Central Florida Research Foundation, Inc., Orlando, FL (US)

( *) Notice: Subject to any disclaimer, the term ofthis patent is extended or adjusted under 35 U.S.C. 154(b) by 0 days.

(21) Appl. No.: 12/459,931

(22) Filed: Jul. 9, 2009

Related U.S. Application Data

(62) Division of application No. 11/044,494, filed on Jan. 27, 2005, now Pat. No. 7,569,127.

(60) Provisional application No. 60/542,564, filed on Feb. 6, 2004.

(51) Int. Cl. BSJC 1100 (2006.01)

(52) U.S. Cl. .................................................... 264/328.1 (58) Field of Classification Search ................ 264/328.1

(56)

See application file for complete search history.

References Cited

U.S. PATENT DOCUMENTS

3,465,774 A 5,580,523 A 5,882,465 A 6,086,825 A 6,251,343 Bl 6,454,924 B2 6,615,857 Bl 6,645,432 Bl

911969 Kautz et al. 12/1996 Bard 3/1999 McReynolds 712000 Sundberg et al. 612001 Dubrow et al. 912002 Jedrzejewski et al. 9/2003 Sinha et al.

1112003 Anderson et al.

64A

66

I lllll llllllll Ill lllll lllll lllll lllll lllll 111111111111111111111111111111111 US007988902Bl

(10) Patent No.: US 7,988,902 Bl Aug. 2, 2011 (45) Date of Patent:

7,595,871 B2 * 2002/0023684 Al 2002/0093143 Al 2002/0124896 Al 2002/0134907 Al* 2003/0206832 Al 2003/0224506 Al 200410017078 Al 2004/0238484 Al *

912009 Weber ........................... 356/246 212002 Chow 712002 Tai et al. 912002 O'Connor et al. 912002 Benett et al. .................. 249/135

1112003 Thiebaud 12/2003 Agrawal et al.

112004 Karp et al. 12/2004 Le Pioufle et al. ............ 264/219

OTHER PUBLICATIONS

Gonzalez, C., et al., "Fluid interconnects for modular assembly of chemical microsysytems", Sensor and Actuators, B, vol. 49, Jun. 25, 1998, pp. 40-45. Pattekar, et al., "Self-Aligning Microfluidic Interconnects for Glass­and Plastic-Based Microfluidic Systems" J. Micromech. Microeng. (2003) vol. 13 pp. 337-345.

(Continued)

Primary Examiner - Jill L Heitbrink (74) Attorney, Agent, or Firm - Brian S. Steinberger; Joyce P. Marlin; Law Offices of Brian S. Steinberger, P.A.

(57) ABSTRACT

A one-piece, microfluidic package with standardized mul­tiple ports allows devices to be connected in series without resorting to extra tubing connections or bonding processes. The one-piece construction consists of microfluidic channels that can be connected to fluid reservoirs and other fluidic components fabricated with interconnecting and interlocking ports. The size of the friction-fit interlocking ports is designed such that the smaller male port fits snugly into the larger female port in a manner that is leak-free and adhesive-free. The friction-fit ports can also be reconfigured. Thus, the inter­connection of microfluidic packages can be in an extended series including connections to sensors and devices such as a bio/biochemical/chemical sensor chip, a dielectrophoretic manipulator chip, and a microfluidic reactor chip.

6 Claims, 8 Drawing Sheets

67

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US 7,988,902 Bl Page 2

OTHER PUBLICATIONS C. Gartner, et al., Polymer Based Microfluidic Devices-Examples for Fluidic Interfaces and Standardization Concepts, Proceedings of SPIE-International Society of Optical Engineering, vol. 4982, pp. 99-104, Jan. 27-29, 2003. Pattekar, et al., "Self-Aligning Mcrofluidic Interconnectors for High Temperature and Pressure Applications" J. Micromech. Microeng. (2003) vol. 13 pp. 337-345.

Puntarnbekar, et al., "Self-aligning microfluidic interconnects for glass- and plastic-based microfluidic systems" J. Micromech. Microeng. (2002) vol. 12 pp. 35-40. Pattekar, et al., "Novel microfluidic interconnectors for high tem­perature and pressure applications" J. Micromech. Microeng. (2003) vol. 13 pp. 337-345.

* cited by examiner

Page 4: Interconnecting Microfluidic Package and Fabrication

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INTERCONNECTING MICROFLUIDIC PACKAGE AND FABRICATION METHOD

This is a divisional of application Ser. No. 11/044,494 filed Jan. 27, 2005, now U.S. Pat. No. 7,569,127 issued Aug. 4, 2009 which claims the benefit of priority from U.S. Provi­sional Application Ser. No. 60/542,564 filed Feb. 6, 2004.

FIELD OF THE INVENTION

2 channels in communication with pillars as shown in U.S. Pat. No. 6,454,924 to Jedrzejewski, et al. The sealing of the mated ports and reservoirs (U.S. Pat. No. 6,251,343 to Dubrow et al.) of the body structure include adhesives, bonding materi­als (U.S. Pat. No. 5,882,465 to McReynolds); negative pres­sure (US Pat. Appln. Pub. 2003/0206832 by Thie baud, et al.); rubber 0-rings (US Pat. Appln. Pub. 2002/0093143 by Tai, et al.); ultrasound welding, thermal processes (US Pat. Appln. 2002/0023684 by Chow), and the like.

10 There is a need for a reliable, easy to manufacture, inex-This invention relates to microfluidic packaging, in par­

ticular to a microfluidic package having integrated, standard­ized interlocking interconnections permitting the combina­tion of multiple sensors and devices.

pensive packaging architecture to make viable fluidic and electrical connections to micro machined microfluidic devices. The present invention provides consumers with an expensive, easy to fabricate, interconnecting, one-piece,

BACKGROUND AND PRIOR ART 15 microfluidic package suitable for snap-in (interlocking) con­

figurations.

Microfluidics is experiencing explosive growth in new products developments. Already there are many commercial applications for electro microfluidic devices such as chemical 20

sensors, biological sensors, and drop ejectors for both print­ing and chemical analysis. The number of micromachined microfluidic devices is expected to increase dramatically in the near future. Manufacturing efficiency and integration of microfluidics with electronics will become important. In 25

order to realize applications for these devices, an efficient method for packaging microfluidic devices is needed.

The biggest stumbling block to commercial success is the lack of general, simple and effective packaging techniques. Packaging of a miniaturized chemical analysis system, also 30

known as a "lab-on-a-chip," is a very important element and plays several roles. Microfluidic packaging has to protect the sensitive functional unit from environmental factors that could affect its performance, like moisture, high temperature, vibration or corrosion. It also has to provide the component's 35

connection to the outside world through electrical, optical and other types of interfaces. Not only should packaging not hinder function in any way, it should be a value-added asset. For example, a microfluidic sensor package would add this value if it contained a tiny pipeline to bring the media to be 40

measured to the device reliably and efficiently. Other con­cepts have the package forming part of the sensing structure itself, becoming part of the device's own complex system instead of just a non-functional casing around it.

It is highly desirable that the MEMS (microelectrome- 45

chanical systems) industry define a standard package for each application category. If a reasonable standard regarding inputs and outputs is available, then one microfluidic package can be appropriate for several different devices.

The present invention could serve as a standardization 50

model for the microfluidics industry. Injection molded microfluidic packages with channels for fluid flow, input and output ports are integrally formed in the molded package. Shapes and sizes of the output ports are standardized and designed to interlock; thus, permitting the interconnection of 55

microfluidic packages in an extended series. For packages that must pipe gases or liquids around on a chip, it will save on resources; it will mean that the entire sensor mechanism does not need to be replaced; just selected modules.

Microfluidic devices and networks in the prior art include, 60

those containing multiple layers as reported in U.S. Pat. No. 6,645,432 to Anderson et al., and sealed by aligning two surfaces and removing a liquid to cause the seal. U.S. Pat. No. 6,615,857 to Sinha, et al. describes linearly arranged flow actuators fastened via bolts. A singular layer whereby the 65

dispensing assembly and chip assembly engage each other with the assistance of alignment members, using vertical fluid

SUMMARY OF THE INVENTION

The first objective of the present invention is to provide a reliable, inexpensive microfluidic package.

The second objective of the present invention is to provide a microfluidic package that affords the integration of the pre-selected, standard sized connecting charmels.

The third objective of the present invention is to provide a microfluidic package of one-piece construction that is easy to manufacture.

The fourth objective of the present invention is to provide a microfluidic package with multiple ports.

The fifth objective of the present invention is to provide an injection molded microfluidic package with various shapes and sizes of ports that are standardized and designed to inter­lock.

The sixth objective of the present invention is to provide a microfluidic package capable of being interconnected in an extended series.

A preferred one-piece microfluidic package include a microfluidic channel and a plurality of ports that engage via a male-female friction fit to permit interconnecting and inter­locking of microfluidic packages in an extended series. In addition to the basic structure of microfluidic charmel and ports the microfluidic package can have at least one fluid reservoir wherein the microfluidic charmel is connected to a fluid reservoir.

A plurality of ports engage via a male-female friction fit that is leak-free and adhesive-free. Further, the plurality of ports are a set of inlet/outlet ports, preferably the set of inlet/ outlet ports has two ports or a multiple of sets of inlet/outlet ports with a corresponding multiple of two ports per set.

With regard to microfluidic package design, the set of inlet/outlet ports has a first inlet/outlet port, sometimes referred to herein as the "male" port, that is smaller than a second inlet/outlet port, sometimes referred to herein as the "female" port. The first inlet/outlet port fits snugly and inter­lockingly into the larger second inlet/outlet port of an inter­connecting microfluidic package.

Attached to the inlet/outlet ports are outlet tubes that have a pre-selected tubing size. The tubing sizes have diameters selected from at least one of approximately 1.58 millimeters (mm) or 1/16 inch, approximately 0.79 mm or 1/32 inch, and approximately 0.396 mm or 1/64 inch. The outlet tubing sizes can also be a standardized size of outlet tubes in the United States (US) and non-US countries and also sized for use in a variety of applications.

The more preferred microfluidic package can be used in interconnections in an extended series including connections to a variety of devices, such as, but not limited to, a biol

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US 7,988,902 Bl 3

biochemical/chemical sensor chip, a dielectrophoretic manipulator chip, and a microfluidic reactor chip.

A preferred method for fabricating a microfluidic package includes selecting a mold cavity with an inlet for injecting a molten polymer, defining a micro pattern of microfluidic channels on a first side of the mold cavity, defining a plurality of inlet/outlet ports on a second side of the mold cavity, injecting a molten polymer into the cavity, allowing the mold to cool, allowing the molten polymer to be come a rigid substrate, and removing the rigid substrate with a microflu- 10

idic channel on a first side and a plurality of inlet/outlet ports

4 FIG. 5 shows one method of fabricating a microfluidic

structure for a one-piece microfluidic package using electro­plating followed by microinjection molding or microemboss­ing.

FIG. 6A is a plan view ofa mold insert with fluid reservoirs connected to fluid channels.

FIG. 6B is a cross-sectional view of the mold insert of FIG. 6A.

FIG. 6C is an exploded view of the mold insert and the alignment of the insert in the mold block.

FIG. 7 shows the injection molding method of fabricating the one-piece microfluidic package.

FIG. SA is a single microfluidic package. on a second side, thereby providing a one-piece, integrally formed, microfluidic package capable ofinterconnecting and interlocking in an extended series.

Preferably, the microfluidic channel is connected to a fluid reservoir in the micro pattern of the mold cavity. The plurality

FIG. SB is a series of three microfluidic packages in an 15 interconnected horizontal arrangement.

of inlet/outlet ports defined in the mold cavity has a first inlet/outlet port that is smaller than a second inlet/outlet port, so that when the microfluidic package is fabricated, the first 20

inlet/outlet port fits snugly and interlockingly into the larger second inlet/outlet port of an interconnecting microfluidic package.

Further, the plurality of inlet/outlet ports can be connected to outlet tubes of a pre-selected tubing size. The tubing sizes 25

have diameters selected from at least one of approximately 1.58 millimeters (mm) (1/16 inch), approximately 0.79 mm (1/32 inch), and approximately 0.396 mm (lf<;4 inch) and other standard sizes in the United States (US) and non-US coun-tries. 30

Various methods for forming the defined structures on the first side of the polymer substrate and the second side of the polymer substrate are used and include well-known tech­niques such as, casting, embossing, machining, and injection

35 molding.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Before explaining the disclosed embodiment of the present invention in detail it is to be understood that the invention is not limited in its application to the details of the particular arrangement shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation.

The microfluidic package of the present invention has tow or multiple integrated interconnections with a pre-selected, standard size or various other sizes with one size fitting into the other. The fluidic interconnector in one component snaps in the fluidic interconnector in another component resulting in interlocking action between the components. This allows the microfluidic devices to be connected in series without resorting to extra tubing connections or bonding processes. The design of the microfluidic package also permits recon­figuration of a series of connections.

The combination of multiple sensors and devices is facili­tated. Furthermore, the one-piece construction of the microf­luidic packaging eliminates complicated alignment processes for attachments as reported in the prior art. In the present

Further objects and advantages of this invention will be apparent from the following detailed description of a pres­ently preferred embodiment that is illustrated schematically in the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES

FIG. lA shows a first side of the microfluidic package with strategic locations of interconnecting inlet/outlet ports.

40 invention, microfluidic channels and containers and other fluidic components are fabricated on the flat side of the pack­age simultaneously or afterwards via injection molding, embossing, casting or various other means. The fabrication method using injection molding guarantees replication of the

FIG. lB shows a second side of the microfluidic package with connecting channels and fluid reservoirs or chambers.

FIG. lC shows the detail and design of male-female inter­locking ports enlarged on a scale of 8: 1.

FIG. 2A shows a perspective view of two four-port microf­luidic packages interconnected.

FIG. 2B shows a plan view of a first side of a four-port microfluidic package.

FIG. 3A is a plan view of a microfluidic package showing a male port, a microfluidic channel and a female port.

FIG. 3B shows cross-sectional views of a male port along line A, A', a microfluidic channel along line B, B' and a female port along line C, C' of FIG. 3A.

45 microfluidic patterns from micro machined molds on one side while generating interconnections on the other side. This saves time and cost involved in post-processing of intercon­nections in various microfluidic devices.

FIGS. lA, lB and lC show structural details of the microf-50 luidic package or device of the present invention. FIG. lA is

a plan view 10 of a first side of a microfluidic package with interconnecting ports lOa and lOb. The smaller port lOa is designed to friction-fit snugly into the larger port lOb, when two microfluidic packages are interconnected. FIG. lB shows

55 a second side 11 of the microfluidic structure with areas

FIG. 3C is an interdigitated array type electrode for dielec-60

trophoretic manipulation.

defined as microfluidic channels 2 and fluid reservoirs or chambers 12. In FIG. lC, a side view 13 of the microfluidic package is shown with interlocking ports 14 and 15. Greater detail and design of each port is enlarged on a scale of8: 1. The smaller port 14a and the larger port 15a have inlet tubes c and d, respectively, wherein the diameter of the tube is approxi­mately 0.50 millimeters (mm). Both ports 14a and 15a have outlet tubes 16 and 17, respectively, with standard tubing diameters such as, approximately 1.58 millimeters (mm) (1/i6 inch), approximately 0.79 mm (1/32 inch), and approximately 0.396 mm (lf<;4 inch). The outer diameter of the smaller male port 14a fits into the larger female port 15a. Standardized

FIG. 3D shows placement of a microfluidic package over the electrode of FIG. 3C to complete the dielectrophoretic cell separation chip.

FIG. 4 is cross-sectional view of serial connections of 65

multiple components using interconnected microfluidic packages.

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US 7,988,902 Bl 5

sizes for outlet tubes 16 and 17 combined with the male­female interlocking function of the ports make this package versatile for use as a common platform between different components. The present invention is suitable for applica­tions using pre-selected, standard size outlet tubes in the United States (US) and non-US countries. The outlet tubes can also be used in a variety of applications.

6 the art can select from a wide variety of materials that are compatible with fluids, devices and testing equipment.

FIG. 2A illustrates the interlocking function of a microf­luidic package, in which two ports in one component 21 are mating with two ports from another component 21a. A first 10

side of the microfluidic package 21 shows the microfluidic channel and reservoir structure 22. The microfluidic structure

FIG. 5 shows a fabrication method for a microfluidic struc­ture with channels and reservoirs created in one side of a microfluidic package. Photolithography defines micro pat­terns on a first side, such as, metal or metallized substrate 50 and electroplating is performed over the open area 51. A photoresist strip 52 is removed and a mold insert is made. The mold insert is used to replicate a pattern on the polymer material 53. It is also possible to use injection molding, cast­ing or embossing to replicate a pattern onto a polymer mate-rial. A side view 54 and a plan view 55 of the completed microfluidic structure shows channels 57 and reservoirs for fluids 59.

is connected to an input port 23 and an output port 24. Fluid flows are injected through the ports, accommodated by the channels and reservoirs in the microfluidic structure and con- 15 FIGS. 6A, 6B and 6C show a fabrication method of the tinue in channels and connections to different devices.

FIG. 2B is a plan view of the embodiment of the present invention, where a four-port design is employed. The smaller male ports 25 and 26 are designed and sized to connect and interlock with the larger female ports 27 and 2S of a different chip or microfluidic package fabricated by the process of the present invention.

FIGS. 3A, 3B, 3C and 3D illustrate how the design of the present invention can be adapted for use as a dielectrophoretic manipulation chip. In FIG. 3A, a plan view 30 of a microflu­idic package is shown with a microfluidic channel 32 fabri­cated on the bottom surface. A smaller port 31 and a larger port 33 are at opposite ends of the microfluidic channel 32 and are connected to channel 32 by fluid channels 3 and 6. FIG. 3B shows a cross-sectional view of inlet/outlet port 31a, the microfluidic channel 32a and inlet/outlet port 33a. The smaller male port 3 la is sized to fit snugly and interlockingly, without the use of adhesives or bonding agents, into the larger female port 33a of an interconnecting microfluidic package.

FIG. 3C is an example of an interdigitated array type elec­trode 34 on a substrate for dielectrophoretic manipulation. It

microfluidic package using mold blocks. In FIG. 6A, a plan view 60 of the mold insert that shows fluid reservoirs 61 and 62 connected to fluid channels 63. FIG. 6B is a cross-sectional view 64 of the mold insert and shows the location of fluid

20 channels 63a and 63b and the raised surface 65 that is used to form the fluid reservoirs. In FIG. 6C, the fabricated mold insert 64a is clamped inside the mold form 66 and aligned with a mold block 67. Inlet and outlet ports in a second substrate 6S are defined by mold block 67, while the microf-

25 luidic structure is defined by mold insert 64 inside of mold block 66. The fabrication of mold block 67 is by a well-known method of EDM (electro-discharge machining) or the same technique illustrated in FIG. 5 can be used.

A preferred method of fabricating the microfluidic package 30 of the present invention is illustrated in FIG. 7, which is a

perspective view of the injection molding process. Injection molding is a well-known process. A clamping block or mold 70 holds a mold insert 71. A molten, fluid polymer or poly­mer-based resin is inserted through nozzle 72 and is then

35 allowed to cool and harden to replicate the pattern of 71, thereby forming a one-piece microfluidic package 73 having microfluidic channels with or without fluid reservoirs on a first substrate and inlet and outlet ports on a second substrate

is understood that the electrode type can vary according to the design chosen by someone skilled in the art and is not a limitation on the present invention. Further, as an example, FIG. 3D shows a fluidic inlet/outlet 35 on the microfluidic 40

that engage by male-female friction fit. FIGS. SA and SB show the microfluidic package of the

package over the electrode and an electrical connection 36 completes the dielectrophoretic cell separation chip.

FIG. 4 illustrates the serial connection of multiple compo­nents with the present invention. Various types of devices and components can share the microfluidic package platform of the present invention and can be configured to have a new synergetic function; the type of device and component is not a limitation of the present invention. In FIG. 4, an interdigi­tated array type electrode on a substrate for dielectrophoretic manipulation 40 receives a fluidic sample injection through an inlet port 41; the fluid flows through interconnected and interlocked port 42, across a biosensor chip 43 and finally through outlet port 45. The arrangement of microfluidic pack­ages in FIG. 4 includes a plan view of a dielectrophoretic manipulator chip 40, a cross-sectional view of connecting and interlocking inlet/outlet ports, 41, 42, and 45, a plan view of the biosensor chip 43 and a cross-sectional view 44 of the biosensor chop 43 along the D, D'.

present invention as an individual package and also as con­nected in a series. In FIG. SA, a single package SO includes a microfluidic structure with inlet/outlet ports SOa and SOb in a two-port design. Interconnected packages Sl are shown in a

45 series where inlet/outlet ports Sla and Slb are at the periph­eral ends of the series. Interconnecting ports Slc and Sld are used to join three individual microfluidic packages in one connected series. It is understood by persons skilled in the art that the interconnecting microfluidic structures could have

50 multiple connections and configurations that extend in verti­cal and horizontal directions as long as there are available inlet/outlet ports that engage by male-female friction fit.

There are many value-added features of the novel microf­luidic package disclosed herein, including, but not limited to,

55 ease of manufacture, and increased utilization of known materials, versatility, reliability, accuracy and economy. The present invention resolves problems in fluidic interconnec­tion by providing standardized, integrated inter-connections that easily combine and reconfigure devices using an inter-Referring now to fabrication methods for the novel microf­

luidic package of the present invention, the packaging can be mass-produced with inexpensive polymer materials. The classes of materials that can be used to fabricate the microf­luidic package include, but are not limited to, acrylics, olefins, polycarbonates, polyesters, polyethylene, polypropylene, polystyrene, polyurethane, poly vinyl compounds, fluorocar- 65

bans, epoxies, silicones and other materials useful in injec­tion molding, casting or embossing. Thus, someone killed in

60 locking action. Thus, a common packaging platform is now available to form a flexible array of devices and components, which include, but are not limited to, a biol chemical/chemical sensor chip, a dielectrophoretic manipulator chip, and a microfluidic reactor chip.

While the invention has been described, disclosed, illus­trated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of

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US 7,988,902 Bl 7

the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modification or embodi­ments as may be suggested by the teachings herein are par­ticularly reserved especially as they fall within the breadth and scope of the claims here appended.

I claim: 1. A method for fabricating a one-piece microfluidic pack­

age, comprising the steps of: a) selecting a mold cavity with an inlet for injecting a 10

molten polymer wherein the mold cavity has a first side and a second side that is opposite the first side;

8 of the mold cavity, and forming a male inlet/outlet port at the first end of the mold cavity sized to connect and interlock with a female inlet/outlet port at the second end of the mold cavity, the first side and the second side together solely providing the one-piece, integrally formed, microfluidic package;

d) injecting a molten polymer into the cavity; e) allowing the mold to cool; f) allowing the molten polymer to become a rigid substrate;

and g) removing the rigid substrate with a microfluidic channel

on a first side and a plurality of inlet/outlet ports on a second side, thereby providing a one-piece, integrally formed, microfluidic package capable of leak-free and adhesive-free interconnecting and interlocking in an extended series.

2. The method of claim 1, wherein the microfluidic channel is connected to a fluid reservoir.

b) defining a micro pattern of microfluidic chamiels on the first side of the mold cavity resulting in a plurality of interconnecting and interlocking ports, that include at 15 least one set of an inlet port and an outlet port, the one set including one male port and one female port, so that the ports engage other ports via a male-female friction fit that is leak-free and adhesive free to permit intercon­necting and interlocking and snapping together of a plu­rality of one-piece microfluidic packages in an extended series, and forming an interior microfluidic chamiel that connects the male port on a first end of the mold cavity to the female port on a second end of the mold cavity, wherein the interior chamiel has a diameter ofless than 25 approximately 1.00 mm;

3. The method of claim 1, wherein the plurality of inlet/ 20 outlet ports has a first inlet/outlet port that is smaller than a

second inlet/outlet port.

c) defining a plurality of inlet/outlet ports on the second side of the mold cavity, the second side having an inlet/ outlet port on a first end of the mold cavity and an inlet/outlet port on a second end of the mold cavity and the plurality of inlet/outlet ports is connected to one of a microfluidic chamiel and a combination of a microflu­idic channel and a fluid reservoir defined on the first side

4. The method of claim 3, wherein the first inlet/outlet port fits snugly and interlockingly into the larger second inlet/ outlet port of an interconnecting microfluidic package.

5. The method of claim 1, wherein the plurality of inlet/ outlet ports are connected to outlet tubes of a pre-selected tubing size.

6. The method of claim 5 wherein the tubing sizes have diameters selected from at least one of approximately 1.58

30 millimeters (mm) (1/16 inch), approximately 0.79 mm (1/32 inch), and approximately 0.396 mm (lf<;4 inch).

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